Telefacsimile recording and duplicating paper and method of making same



May 12, 1953 A. G. cooLEY ETAL 2,538,422

. TELEFACSIMILE RECORDING AND DUPLICATING PAPER AND METHOD OF MAKING SAME Original Filed March 24, 1942 III /Z TATE. :22

Aus 70v 0001i? fiq p p WA IN'VENTORS Patented May 12, 1953 4. UNITED TELEFAGSIMILE CATING PAPER AND METH D or MeKi 'Austin G. Cooley, New York,- N.- Y., and Harold R.

New Work ori inal "'{Ifhis invention relatesto electrosensitive re-- cording and duplicating "blanks, and "mdle'eS- pecially to blanks Whichare responsive to stylus-applied electric signals to produce-"avisible record thereon;

In the case of messagetransmission 'by 'elec-" tro-"-facsimile' techniques" it is not always po's' sible or advisible torep'eat -the facsimile trans m'i'ssioni and yet it maybe necessary to' use' "the tno sen'sitivi'ty to' 'stylus japplied electric signals m t sh carefully controlled and maintained, especially since theblank must'have uniformity of electrosensitive 'iresponse over'its entire area.

We have found that in order to achievethis de-" sire unformity of .electroresponse, and at the same time to enable the blank to be used as a duplicating master, particularly vvhemthe; due plication is by contact with a moistened hectograph ormimeographr-pad; care mustbe. exer-v ci'sed-in-the choiceand-=-relative--location of the variousilayers or ingredients which constitute themamka According-1y,- it is one of the principal objects of this invntio n tq provide an--;improved-elect sen i ivear rdin wand. duplicating b a and one which exhibits substantially uniforni responsev over its -entirearea to a. given stylusapplied electric signal. I r

I Fig, 1 Tis I'an enlarged cross-sectional viewof part 'jjo f; an electrosensitive recording arid...,duplicitingbltink according to thefinventioni.

Fig'f2isa modification of Fig. ll I Fig. 3 is a diagrammatic view of a facsimile recording and duplicatinggsystem for using the blank according to the invention.

Referring-to Fig. 1f, the sfacsimile frecordingiand duplicatirlg-rblank according to the" invention comprises a base or carrier I of paper, although other pliable materials such. as fabric, photographic transparencies, orithe like, may be employed. The paper I is provided with two superposed coatingspriilayers 2, 3. Coating 2 is es p c y ned so th t i ad ion oiha n the desired electrical conductivityv through its thickness, it, also acts as, a .retainer for a dye] or dyes which control, the subsequent tluplieating; stepassur s-i i aia eisdantics-las it :ture and also with a: suitable binder or adhe- Dalton, Jnkintown; Pa., assignorsitoTimefax i Corporation; New York, Nays, aacorpotationof.

1 8 Claims. (Cl.

extremethinness, and acts as a protective or 'sealingtco'atingT for the duplicating coating 2. TheIcoatingS, for convenience, is referred to herein as the facsimile or masking coating.

Theblankcanbe used to receive and record electric signalsisuch as facsimile ortelegraph sigrialsby well-known .telefacsimile procedure.

. electric signals can.either- .be in the form of an electric space dischafg' 'tb'jar' through the coating'3'," 'fo'i egampie" means of cur-rent which- 1s caused to flow conductively through the transverse cross-section of the blank. Where therecording is effected by an electric space discharge'such as a corona discharge, as described in U. S. Patent #1,702,595 wres le. QQ BX lhs has? ma e. ci con noting paper (Fig. 2).; If the recording is elec ed-tr ra srerse cqo u t vity, through t e entire plank includingthe, base. the base I may bst al y-conducting aper. s- 1 will be ersto9d, therefore, that the base paper, be L either non;-conducting or substantially, non conducting,or it may be specially treated torender it of the desired conductivity in raccordance .with the particular type of electric currentthat is used for recording, that is whether.-a;space.:discharge-current or a transverse conductive current.

' If thgibase l is of the non-conducting type, it

may be a Well-known white or colored paper upon which is-applied a black conducting layer containing electrically-conductive carbon such :as gas black mixed with a dye or dye mix- Siye. .For c zonvenience of description, the layer 2 containingthe electricallyconductive carbon and .the-ldyeiyvill be referred to herein as the duplicating layer orcoating; The layer or coating 3' which "will be referred to herein as the facsimile coating, consist-sof a pigment, usually white, to contrast with the black coating '2, the said pigment being incorporated with a suitable adhesive or binder.

In accordance withthe invention, the electricallyconducting coatingfl comprisesgfor example, gas black 'mixed' with a Water soluble binderf such as gelatin, gum starch, casein, cellulos'e ethergxorgv cellulose .ester,.. and a 1 suitable AI XJsuitabledye canJbe incorporatedin the bla'ck coating' i l-solong asthe desired electric "conductivity of. the-blank is not seriously Impaired. Dyes, like-crystal violet; methyl violet,

5s m sstat ent; Stress wate qlubie ni lQ'r,

b50115. discharge; or by' sine, chrysoidine brown, etc., or any combination of such dyes, can be used.

In using the binders above mentioned, it is desirable to use as little binder as possible, and in general the amount of binder may vary from to of the dry weight of the carbon or gas black.

The binder that is used for the coating 3, should be chosen so that there will be little, if any, tendency for the two coatings to intermingle when coating 3 is applied over coating 2. Also it is necessary to select the proper combination of binders and solvents for both coatings, so that the dye of coating 2 will be very soluble in its solvent, and will be well distributed when dry, but will not mingle with the facsimile coating 3 when the latter is applied. Since the coating 3 acts as a masking or protective coating for the dye-bearmg coating 2, and since it is the coating 3 that is exposed during handling of the blanks, it is important that the binder that is used for coating 3, be water insoluble, otherwise the blank would be subject to water spotting and smearing, due to handling. In other words, the coating 2 should, in accordance with the invention, incorporate a water soluble binder, and the coating 3 should incorporate a water insoluble binder. The fol- IOWil'lg is a typical example of a mixture that may be used for the coating 2:

Example I 5.0 grams of gas black (Dixie #5 manufactured by the United Carbon Company, Inc.)

2.0 grams Methocel (15 cps, manufactured by the Dow Chemical Company) 4.0 grams crystal violet 55.0 cc. water The Methocel is dissolved in a portion of the water and the gas black added while stirring.

The dye is added to the remaining water and heated slightly to dissolve it completely. A small amount of glycerol, C'arbitol or the like material may be added to increase the solubility of the dye. The mixture is then passed through a colloid mill or similar device and applied to the paper by any of the normal coating methods, such as spraying, dipping, brushing, or knife coating, etc. After coating the paper, the liquid contained in the binder is evaporated off by heating or any other suitable method. The paper may thereafter be subjected to calendering in order that the surface may be smooth.

The following is another example of a mixture that can be used for coating 2:

Example II In this instance a combination of dyes was selected to produce a black color. The polyvinyl alcohol is dissolved in a portion of the water and the gas black added. The dyes are dissolved in the remaining water by heating slightly and added to the black dispersion. Thereafter the mixture is passed through a colloid mill or'similar device before application to the paper. The application may be by any of the methods suggested hereinabove, and of course, includes the steps or light colored pigment and a binder.

of evaporating the liquid from the binder and of calendering if necessary.

For facsimile paper purposes the paper after coating with the first or conducting coating 2 is further processed with the second or facsimile coating 3. This latter coating consists of a white The binder utilized may be any one of those mentioned in connection with the conducting coating, but as has been stated it should be a binder soluble in organic solvents for the facsimile coating, and one soluble in water for the conducting coating. Amongst the pigments which are satisfactory for use in the facsimile coating may be mentioned zinc sulphide, zinc oxide, barium sulphate, ba-

rytes, blanc fixe, lithopone, titanium dioxide, and the like. The sensitivity of some of these pigments may be improved by incorporating in them a small percentage, approximately 0.2 to 1.0%, of either mercuric sulphide, red or yellow lead oxide, stannic sulphide, etc. Of course it must also be kept in mind to so select the solvent for the facsimile coating so that the ingredients from either coating will not mingle.

The amount of the facsimile coating necessary to produce a satisfactory recording paper is very small. The exact amount cannot be stated since variation in weight of the paper and variation in thickness of the black conducting coating will cause variations which make it difficult to meas- The following are examples of suitable mix-' tures for the facsimile coating 3:

Example I 60.0 grams zinc oxide 0.3 gram mercuric oxide 15.0 grams of lacquer base consistingof 10% B. R. 254 resin manufactured by the Bakelite Corporation, 75% Ethocel, l0 cps Standard;

manufactured by the Dow Chemical Company and 15% of No. 6 Plasticizer manufactured by the Dow Chemical Co. 125.0 grams solvent consisting of 70% toluol and 30% ethyl acetate.

The lacquer base is dissolved in the solvent and the zinc oxide and mercuric oxide thereafter added. The mixture is then passed through a colloid mill or other imilar device before application to the paper, which application may be by any of the methods herein mentioned.

Example II This example is similar to the above except rivative.

60.0 grams zinc oxide 0.3 gram mercuric oxide 18.0 grams of lacquerbase consisting of 15% ester gum manufactured by the American Cyanamid 8r Chemical Corporation, 70% nitro cellulose 2 second and 15 of No. 6 Plasticizer manufactured by the Dow Chemical Company.

140.0 grams solvent consisting of 70% toluol, 25%

ethyl acetate and 5% denatured alcohol.

' The lacquer base is dissolvedin' thesol'vent and the zinc oxide "and. 'mercuric'oxide there,- after added. The mixtureis prepared" and ap-* plied by any of the methods herein mentioned.

Referring to Fig. 3,.there is ishown imgenera alized schematic form, a .telefa cs'imilef recording and duplicating system wherein the numeral 5: represents any well-known form of 'telefacsimile: transmitter whereby the subject matter to be transmitted is scanned in'succe'ssive' are'a's"of'ele-' mental size to produce corresponding electric signals. Thesesignals are transmitted over'a suitable transmission channel 6 to' the facsimile. receiver 1, the output of whichlenergizesithe recording needle 8 with a- 'coronaproducing voltage whose effective recordingvalue-is determined by the received telefacsimildsignals. The needle 8 is slightly spaced from the recordingblank 9 which is carried by the rotating dnum Ill. The drum is rotated and advanced longitudinally; in any manner well-known. in K the facsimile scanning arts and in synchronism with the corresponding scanning equipment --'at the transmitter 5. The recording blank 9=is formed of a'base-of paper having two superposed layers correspondingrespectively to layers 2 and- 3-of Fig. 1. As a result of the corona discharge from needle electrode 8,-the outeror facsimile-layer 3 is removed at the =points-corresponding-to the original subject matter scanned atthe transmitter 5 thus exposing the dye-carrying transfer layer 2. s The subjectmatter -is' therefore-directly-producedon the blank- 9 and--this blank-may be removed and its surface-moistened-by a-suitable solvent for-the dye in coating-d but which solvent does not aifect the coating -3.-- This moistened record blank can-then-be-used-as --a' matrix to transfer the recorded subject matter any desired number of times to any suitable receiving surface such as to a succession of paper sheets I l. fljhe transfer ofthe moistened dyerecord' from blank--9 to--thecopysheets I I can be done eitherzdirectlxiasldescribedi;1011;indirectly by .,fDitto or Hectograph process, Qflhusthe dye record on blank QLcanbe transferred-by contact with a hectograph blank 12 comprising an aqueous solvent held by a moistened gelatin glycerol compound which receives the impression in reverse from the master record and transfers it to the paper or sheet material in readable form by bringing the two in contact with each other. Water is used as the solvent for the copying machine process and alcoholsolutions for the spirit process.

The copying facsimile paper of this-invention can be used to produce copies either from aqueous or alcoholic solvent processes and by proper selection of the dye in coating 2 and binder base in coating 3 can be made to operate using other solvents if occasion arises.

The number of copies that can be obtained from a single facsimile recording used as a master record is also very large, larger than for any known master records using the described method of copying, and a distinct feature of this particular combination of paper and coatings. This results from the fact that the master record holds or can be made to hold large quantities of dye and the master record can be used over and over again to produce fresh impressions on the gelatin-glycerol compound. Over 1,000 clear legible copies have been made from a facsimile recording.

Various changes and modifications may be made in the disclosed embodiments without departingfr'om the-spirit and scope of; the invention.

--This applicationis a division of application filed March 24, 1942, now

with elctrically conductive carbon with a water soluble binder and with water, applying said mixturetolthe surface of abacking to form a duplicating OOatE OE predetermined electric conductivity, drying the said mixture on said backing, mixing a pigment with a binder soluble in an organic solvent and with such organic solventin which said dye and the first-mentioned binderare insoluble, applying the second-men-. tioned mixture over'the first-mentioned mixture.

with a thinness merelyisufiicientisto .maslo the color. of -said dye and: of said carbon,.. and. then drying said second'mixture-toform a non-tacky homogeneous and pigment-bonded maskingaicoat over the -firstumixture which masking :coat is locally removable in elemental :areasxin response: to electricidischarge produced .by said stylus-ape plied electric signal-voltages. i c 2. -A--blank specially adaptedformaking a duplicating and directvisual record 'of 'electric faCi-T simile signals-stylus-applied thereto, ecompris ing a pliablmbackinghaving a dry top surface.

coat -which isremovaible iii-minute areas sharper ly-l'ocalizedbeneath the point' of an electrically energized needle stylus-, a dry duplicating 'coat sandwiched *between'. said-backing Land; said top.

coat; said duplicating coat having incorporated herein -a predetermined quantity =of electrically conductive carbon"=together with a: binder and a transferable dye to constitute andmaintain said duplicatingcoat,-saidtop-coaflcontaining a pigmenvbonded therein 'and bein'g of a thinness sufficient tc niaslt said dye' and sjaid electrically conducting carbon, the said dye and binder of the duplicating coat being insoluble in the solvent for said top coat.

3. A blank specially adapted for making a duplicating and direct visual record of electric facsimile signals stylus-applied thereto, comprising a pliable backing having a dry top surface coat which is removable in minute areas sharply localized beneath the point of an electrically energized needle stylus, a dry duplicating coat sandwiched between said backing and said top coat and having incorporated therein a predetermined quantity of electrically conductive carbon together with a water soluble binder and a water soluble transferable dye to constitute and maintain said duplicating coat an electrical conductor, said top coat being nontacky and forming a sealing and protective coat for the dye in said duplicating coat, said top coat containing a pigment and a binder for the pigment and which binder is water insoluble and being of a thinness merely suiiicient to mask said dye and said electrically conductive carbon.

4. A blank specially adapted for making a duplicating and direct visual record of electric facsimile signals stylus-applied thereto, comprising a pliable non-conducting paper backing having a dry top surface coat which is removable in minute areas sharply localized beneath the point of an electrically energized needle stylus, a dry duplicating coat sandwiched between said backing and said top coat and having incorporated therein a predetermined quantity of electrically conductive carbon together with a water soluble binder and a water soluble trans- Sera'cle dye to constitute and maintain said duplicating coat an electrical conductor, said top coat being non-tacky and including a masking pigment permanently bonded therein and a Water insoluble binder therefor to form a sealing and protective coat for the dye in said duplicating. coat, said top coat having a thinness merely sufiicient to mask said dye and said electrically conductive carbon.

5. A blank specially adapted for making 'a duplicating and direct-visual record of electriciacsimile signals stylus-applied thereto, comprising a non-conductive paper backing having adry top surface coat which is removable in minute areas sharply localized beneath the point of an electrically energized needle stylus, a dry duplicating coat sandwiched between said back-' ing and said top coat and having incorporated therein a predetermined quantity of electrically conductive carbon together with a water soluble binder and a water soluble transferable dye to constitute and maintain said duplicating coat an electrical conductor, said top coat including a pigment and a water insoluble resin binder therefor and which is'non-tacky when dry to form a sealing and protective coat for the dye in said duplicating coat. said top coat having a thinness jnierely sufficient to mask said dye and said electrically conductive carbon.

6. A blank specially adapted for making a duplicating and direct visual record of electric facsimile signals stylus-applied thereto, comprising a paper backing having a dry top surface coat which is removable in minute areas sharply localized beneath the point of an electrically energized needle stylus, a dry duplicating coat sandwiched between said backing and saidtop coat and having incorporated therein a predetermined quantity of electrically conductive carbon together with a watersoluble polyvinyl alcohol binder and a water soluble transferable dye to constitute and maintain said duplicating coat an electrical conductor, said top coat including a whitish pigment together with a water insoluble resin binder therefor and which is non-tacky when dry to form a sealing and protective coat for the dye in said duplicating coat, said top coat having a thinness merely sufficient to mask said dyes and said electrically conductive carbon while being smoothly continuous and non-powdering.

'7. A unitary multi-layer blank specially adapted for recording and duplicating electric signals stylus-applied thereto, said layers being integrally bonded to form a unitary composite single sheet which retainsits single sheet character both during recording and duplication,

said blank comprising a paper backing layer,

a dry, top facsimile layer which is removable in localized areas in response to electric signals stylus-applied thereto, said top layer comprising a pigment bonded in a water insoluble binder, a dry duplicating layer sandwiched between said backing layer and said top layer and comprising electrically conductive carbon with a water soluble binder and a water soluble transferable dye, said duplicating layer being an electrical conductor, said top layer being non-tacky and being integrally bonded to said duplicating layer and to said paper layer to form a single sheet both during recording and duplication, said top layer being of minimum thinness consistent with the desired masking of said dye and said electrically conductive carbon.

S. A blank according to claim 7, in which said top layer comprises a dried mixture of said pigment and a water insoluble resin binder.

AUSTIN Gr. COOLE Y. HAROLD R. DAL-TON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,188,590 Bjorksten Jan. 30, 15340 2,294,150 Kline Aug. 25, 1942 

1. THE METHOD OF MAKING A RECORDING AND DUPLICATING BLANK WHICH IS SPECIALLY ADAPTED TO RECORD ELECTRIC SIGNAL VOLTAGES STYLUS-APPLIED THERETO, WHICH COMPRISES MIXING TRANSFERABLE DYE WITH ELECTRICALLY CONDUCTIVE CARBON WITH A WATER SOLUBLE BINDER AND WITH WATER, APPLYING SAID MIXTURE TO THE SURFACE OF A BACKING TO FORM A DUPLICATING COAT OF PREDETERMINED ELECTRIC CONDUCTIVITY, DRYING THE SAID MIXTURE ON SAID BACKING, MIXING A PIGMENT WITH A BINDER SOLUBLE IN AN ORGANIC SOLVENT AND WITH SUCH ORGANIC SOLVENT IN WHICH SAID DYE AND THE FIRST-MENTIONED BINDER ARE INSOLUBLE, APPLYING THE SECOND-MENTIONED MIXTURE OVER THE FIRST-MENTIONED MIXTURE WITH A THINNESS MERELY SUFFICIENT TO MASK THE COLOR OF SAID DYE AND OF SAID CARBON, AND THEN DRYING SAID SECOND MIXTURE TO FORM A NON-TACKY HOMOGENEOUS AND PIGMENT-BONDED MASKING COAT OVER THE FIRST MIXTURE WHICH MASKING COAT IS LOCALLY REMOVABLE IN ELEMENTAL AREAS IN RESPONSE TO ELECTRIC DISCHARGE PRODUCED BY SAID STYLUS-APPLIED ELECTRIC SIGNAL VOLTAGES. 